For the banana-strawberry muffins, mix flour and baking powder with the strawberry chips. In a mixing bowl, mash the bananas, add the yogurt, then add the eggs, sugar, flour mixture and oil in order.
Line a muffin pan with paper cups, pour 2 large tablespoons of the mixture into each well. If desired, place a slice of banana on top of each muffin. Bake the banana-strawberry muffins in a preheated oven at 180 degrees for about 20 minutes.